Add SVG Favicon output support

[MrWook]

The main desktop browser are supporting SVG favicons. https://caniuse.com/#feat=link-icon-svg
This library already supports svg as an input field but doesn't have a svg output, as far as I can see.
Would be cool if this will be implemented.

[RplusSoundOn]

svg favicon with fallback

<link rel="icon" type="image/svg+xml" href="/favicon.svg">
<link rel="alternate icon" href="/favicon.ico">
<link rel="mask-icon" href="/safari-pinned-tab.svg" color="#ff8a01">

https://css-tricks.com/svg-favicons-and-all-the-fun-things-we-can-do-with-them/

[MrWook]

@RplusSoundOn i know how it should look like in the html.
This library has a html output where the svg output is missing

[alexander-akait]

PR welcome

[IdkMan2Usertive]

Upvote 👍🏼

[juanca]

Is it okay if the feature only supports SVG as an output if and only if the input is an SVG? It would be the easier than converting PNGs to SVGs 😅